Charging the battery still its on the vehicle

[vitz]

Guys,

Fuel crisis lead most of us to leave the car in the Garage for an extended period of time. It would be good to charge the battery as today's price of a car battery is barely affordable!!!

Could an expert shed your thoughts on DIY steps of charging the battery when it is still on the car. Two things especially

1. The need of disconnecting battery terminals before charging, to avoid any possible damages to the ECU

2. Leaving the car batter disconnected: is it okay for an extended time. 

3. What is the voltage we should keep the battery. (e.g. something as below)

4. If we need to remove terminals, how to avoid loss of memory.

I am mentioning about modern cars here!!!!!

 

[iRage]

Wouldn't a trickle charger work here rather than a proper full charger ? They prvide a very low level of current that it will not hurt the electronics of the car by over charging the battery. There are fancier ones (I think they are called Auto Trickle chargers or auto battery maintainer or something) which goes in to stand by mode when it detects the battery is charged within a certain threshold.

[tiv]

What I do is pop off the negative terminal, connect it to the charger and let it do its thing, but nothing that I own has that issue where the electronics go crazy when the battery taken is off. I do it on a two weekly schedule for the cars I don't use.

My intent here is to purely save the battery as batteries have gone to abysmal prices.

I was told that even trickle chargers can harm the ECU bits if the power goes on and off from the CEB mains, even given that they take time to initialize and scope the battery before applying the charge. 

Of Course we don't find the high end ones like the stuff celebrities have in their garages in other countries. 

 

Average car with a good 45A- 65A battery shows like 12.5v in the morning, and like 12.7v just after a run with engine off. That 12.7- will go to like 12.4 within minutes if you keep the blower or stereo on without the engine running. If you drain it to like 11.9- 11.8 might not crank for more than 5 seconds. This again if its a very good condition battery, 

FYI I own a 2018 Vitz and have had no issues in removing the battery plugs, the stereo is a pioneer one so no code issues. 

Edited July 6, 2022 by tiv

[vitz]

10 hours ago, tiv said:

What I do is pop off the negative terminal, connect it to the charger and let it do its thing, but nothing that I own has that issue where the electronics go crazy when the battery taken is off. I do it on a two weekly schedule for the cars I don't use.

My intent here is to purely save the battery as batteries have gone to abysmal prices.

I was told that even trickle chargers can harm the ECU bits if the power goes on and off from the CEB mains, even given that they take time to initialize and scope the battery before applying the charge. 

Of Course we don't find the high end ones like the stuff celebrities have in their garages in other countries. 

 

Average car with a good 45A- 65A battery shows like 12.5v in the morning, and like 12.7v just after a run with engine off. That 12.7- will go to like 12.4 within minutes if you keep the blower or stereo on without the engine running. If you drain it to like 11.9- 11.8 might not crank for more than 5 seconds. This again if its a very good condition battery, 

FYI I own a 2018 Vitz and have had no issues in removing the battery plugs, the stereo is a pioneer one so no code issues. 

My case too, the problem will be resetting the controls of pioneer stereo. Anyways, I am planning to connect a UPS battery as a back up during charging!!!!!

Looks it would be safer to remove the negative terminal and do the charging. I got a variable current charger got from Dxxz.

By the way, would it make issues if  a car left without starting for long time?

[iRage]

7 hours ago, vitz said:

By the way, would it make issues if  a car left without starting for long time?

Depends on your definition of long time...

but yes...

It is best that the engine gets cranked so that the internals move and let the fluids circulate a bit. If not, the metal on metal contact points will be a bit rough at start up after a long time...also, the rubber hoses, seals, etc..need to have fluids passing through them at operating temp. This applies to transmission, brakes and even shocks...

Also, the tires need to rotate and reach proper op temp as well...if not the rubber starts cracking, gets hard, and stuff.

So ideally...please plan on at the very least starting up the engine, and if possible just rolling it back and forth for awhile every week or few weeks. Having said that...your car is not going to break down in to pieces if you don't start it up for 3 or 4 weeks...it is just that when you start her up after..lets say 4 weeks...you just need to let the fluids circulate before driving off and even when you do you need to start doing so gently. Check the thread on long term storage of a car...prettymuch everything there applies to simply not using the car.